Data mirroring is a technique used to enhance reliability in data storage arrays. In a typical storage array that employs data mirroring, the mirroring can be accomplished by writing the information at two different locations. Some systems write the information 180 degrees out of phase on the same disc; thus, reducing the capacity of the drive by at least half. On the other hand, some systems write the data from one disc drive onto a second disc drive in the array; this method requires having a second drive for every first drive in the array. These systems require twice as much data storage space to meet the non-mirrored design requirements. Consequently, such systems can be expensive and inefficient.
Therefore, a need exists for a system of providing data mirroring at a more efficient rate and lower cost. More specifically, a need exists for a solution to the problem of mirroring fast input/output drives, while reducing the cost incurred in mirroring without decreasing the system performance.
Therefore, there is a need for an improved system and method of data mirroring in a data storage device.